Multi-service-class definition type ATM switch

ABSTRACT

A multi-service-class definition type ATM switch is basically configured by an ATM buffer device containing buffers, a data input/output device and a data processing device. The data input/output device inputs data with regard to a service class including a service category (e.g., VBR, CBR) and a QOS class, which the user needs. The data are transmitted to the data processing device, wherein the data are subjected to analysis. Herein, the data designate a buffer number and a request type, which represents one of three modes. At a data setting mode, the service class is set to the buffer designated by the buffer number within the buffers. Then, the data input/output device displays result of the setting. At a data read mode, the data are read from the buffer designated by the buffer number and are then output (or displayed) by the data input/output device. At a data renewal mode, new data are added to data storage, or unnecessary data are deleted from the data storage, so that the data input/output device displays result of renewal.

This is a continuation of application Ser. No. 09/313,079 filed May 17,1999, now abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to ATM switches which use buffers to cope withmultiple service classes containing service categories corresponding toCBR, VBR and Best Effort Classes, for example.

This application is based on Patent Application No. Hei 10-137175 filedin Japan, the content of which is incorporated herein by reference.

2. Description of the Related Art

Conventionally, there are provided a variety of technologies regardingthe ATM networks and ATM switches (where “ATM” is an abbreviation for“Asynchronous Transfer Mode”).

For example, the paper of Japanese Patent Application, Publication No.Hei 7-240752 discloses an example of the ATM switch which is designed tomanage communication quality with respect to every service class.Herein, quality control is made by the setting of a switching path inresponse to QCC tags representing quality classes for services requestedby cells.

The paper of Japanese Patent Application, Publication No. Hei 7-193583discloses an example of the ATM multiplexing processing employed in theB-ISDN subscriber access system (where “B-ISDN” is an abbreviation for“Broadband Integrated Services Digital Network”), which provides anefficient and fair way for use of resources of the networks. Herein,input cell data are subjected to classification according to QOS (i.e.,quality of service) classes and scheduling control while connectionstate management is effected between the network operator and ATMmultiplexing processing device.

The paper of Publication No. Hei 9-507738 (which publishes the contentsof Japanese translation of the International Patent Application No.PCT/FI95/00282, International Publication No. WO95/32570) discloses anexample of the technology for prioritization of traffics in the ATMnetworks. Herein, cells are transmitted by means of buffers which areexclusively provided for a specific service class within differentservice classes of the ATM network. In order to concentrate resources onthe subscriber application(s) at a time while maintaining the trunknetwork as simple as possible, division of the service classes is madeby only the VPI (i.e., virtual path identifier) of the header of thecell.

The paper of Japanese Patent Application, Publication No. Hei 7-321796disclose a virtual path shaping device for the ATM network, in whichcells of different service qualities are accumulated in differentbuffers respectively, so that the cells of high-quality service arefirstly output.

The paper of Japanese Patent Application, Publication No. Hei 10-13416discloses an example of the ATM switch which provides output bufferswith respect to different service categories corresponding to CBR,RtVBR, NrtVBR and Best Effort classes (where “Rt” denotes “real-time”while “Nrt” denotes “non-real-time”). Each of those buffers is given aspecific degree of priority in cell transfer. Herein, only when cells donot exist in all of the high-priority buffers, the cell transfer isperformed

In addition, estimation is performed using the conventional real-timecall acceptance control method, which merely copes with a single class,to estimate a cell loss ratio for the traffics multiplexing calls ofmultiple service categories. After the estimation, the cell loss ratiofor the low-priority service category is estimated under an assumptionthat all of the lost cells belong to the low-priority service category.

As described above, the conventional technology is designed to executethe cell transfer only when the cells do not exist in all of thehigh-priority buffers within the output buffers of the ATM switch, whichare provided to cope with the different service categories respectivelyand each of which is given a specific degree of priority in celltransfer.

FIG. 9 is a block diagram showing a configuration of the output buffersprovided within the ATM switch. Herein, there are provided four types ofthe buffers, i.e., CBR buffers, RtVBR buffers, NrtVBR buffers and “BestEffort Classes” buffers. Using a multiplexer and the above buffers, itis possible to configure an apparatus and method for multi-service-classATM call acceptance control.

However, the aforementioned technology suffers from problems, asfollows:

-   -   (1) In the case where the user needs only a certain service        category (e.g., CBR) within the service categories, it is        unnecessary to provide the buffers regarding the other service        categories. In this case, there occurs a reduction in a use        efficiency of the buffers. Because, the ATM switch lacks a        function to define the buffer(s) to be related to only the        service category which is requested by the user.    -   (2) The conventional technology designs the ATM switch such that        the buffers are fixedly used for the prescribed service        categories respectively. So, the ATM switch cannot cope with        addition of a new service category and deletion of the service        category. Because, the ATM switch lacks a function to define the        buffer(s) to cope with the addition and deletion of the service        category.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a multi-service-classdefinition type ATM switch that is capable of defining buffers to berelated to multiple service classes containing service categories.

It is another object of the invention to provide a multi-service-classdefinition type ATM switch that is capable of coping with addition anddeletion of the service category.

Basically, this invention is characterized by an improvement of the ATMswitch, which provides brand-new functions that the user is capable ofdefining the service classes such as the service categories and QOSclasses for the buffers within the ATM switch.

To secure the aforementioned functions, the ATM switch of this inventionaccomplishes basically four elements in operations, as follows:

-   -   i) A data input section is provided to input the buffer number        representative of the buffer for which the user wishes define        the service class.    -   ii) The data regarding the service class are transmitted to the        ATM switch, wherein the data are subjected to analysis to        specify the service class which should be defined for the buffer        within the buffers.    -   iii) The ATM switch executes the data setting (or definition of        the service class) with respect to the corresponding buffer.        Then, processing result in the data setting (or definition) is        transmitted to the data input/output device. So, a data output        section outputs (or displays) the processing result.    -   iv) As for addition or deletion of the data regarding the        service class and QOS class, the user issues a renewal request        of the data by means of the data input section. Then, the data        are renewed (e.g., added or deleted) and stored in the data        storage sections provided within the data input/output device        and data processing device respectively.

This invention describes a multi-service-class definition type ATMswitch, which is basically configured by an ATM buffer device containingbuffers, a data input/output device and a data processing device. Thedata input/output device inputs data with regard to a service classincluding a service category (e.g., VBR, CBR) and a QOS class, which theuser needs. The data are transmitted to the data processing device,wherein the data are subjected to analysis. Herein, the data designate abuffer number and a request type, which represents one of three modes.At a data setting mode, the service class is set to (or defined for) thebuffer designated by the buffer number within the buffers. Then, thedata input/output device displays result of the setting. At a data readmode, the data are read from the buffer designated by the buffer numberand are then output (or displayed) by the data input/output device. At adata renewal mode, new data are added to the data storage or unnecessarydata are deleted from the data storage, so that the data input/outputdevice displays result of renewal.

Thus, it is possible for the user to freely define (i.e., set, add,delete or renew) the service classes containing the service categorieswith respect to the buffers arbitrarily selected from the ATM bufferdevice.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects, aspects and embodiment of the present inventionwill be described in more detail with reference to the following drawingfigures, of which:

FIG. 1A is a block diagram showing a configuration of an ATM bufferdevice provided within an ATM switch in accordance with embodiment ofthe invention;

FIG. 1B is a block diagram showing a configuration of a datainput/output device provided within the ATM switch;

FIG. 1C is a block diagram showing a configuration of a data processingdevice provided within the ATM switch;

FIG. 2 is a flowchart showing operations of the ATM switch;

FIG. 3 is a flowchart showing operations of the ATM switch at a datasetting mode;

FIG. 4 is a flowchart showing operations of the ATM switch at a dataread mode;

FIG. 5 is a block diagram showing a concrete example in definition of aservice class with respect to buffer 1 in the ATM buffer device;

FIG. 6 is a block diagram showing configurations of selected parts ofthe ATM switch in accordance with another embodiment of the invention;

FIG. 7 is a flowchart showing operations of the ATM switch of FIG. 6;

FIG. 8 is a flowchart showing operations of the ATM switch of FIG. 6 ata data renewal mode; and

FIG. 9 is a block diagram showing a part of the conventional ATM switchhaving output buffers which are provided to cope with different servicecategories respectively.

DESCRIPTION OF THE PREFERRED EMBODIMENT

This invention will be described in further detail by way of exampleswith reference to the accompanying drawings.

FIGS. 1A, 1B and 1C are block diagrams showing configurations ofselected parts of an ATM switch, which is designed in accordance withthe preferred embodiment of the invention. Specifically, FIG. 1A shows aconfiguration of an ATM buffer device 1; FIG. 1B shows a configurationof a data input/output device 2: and FIG. 1C shows a configuration of adata processing device 3.

The ATM switch contains the ATM buffer device 1, the data input/outputdevice 2 and the data processing device 3. Herein, the ATM buffer device1 is provided at either the input side or output side of the ATM switch,or the ATM buffer devices are respectively provided at both of the inputside and output side of the ATM switch. In addition, the datainput/output device 2 is configured as “NMS” (i.e., Network ManagementSystem), which inputs and outputs data of service classes and/or whichreceives and transmits data of service classes.

As shown in FIG. 1A, the ATM buffer device 1 is equipped with a buffersection 11 and a cell read section 12.

The buffer section 11 contains maximally “N” buffers (e.g., eightbuffers), which are named as “buffer 1”, “buffer 2”, . . . , “buffer N”respectively. Before the user defines data of service classes, all ofthe buffers are not defined in relation to the service classes.

The buffer section 11 as a whole has a function to accumulate and/ortransmit cells for every service class after the service class isdefined so that the ATM switch accepts calls with regard to the serviceclass.

The cell read section 12 has a function to read and transmit cellsaccumulated in the buffers of the buffer section 11.

As shown in FIG. 1B, the data input/output device 2 is equipped with adata input section 21, a data transceiver section 22 and a data outputsection 23. Herein, the data input section 21 has a function to enterdata using “GUI” (i.e., Graphical User Interface), for example.

The data transceiver section 22 has a function to tranmsit data to thedata processing device 3 of the ATM switch as well as a function toreceive data from the data processing device 3 of the ATM switch.

The data output section 23 has a function to visually display data on ascreen of a display (not shown).

As shown in FIG. 1C, the data processing device 3 is equipped with adata transceiver section 31, a data analysis section 32 and a datareading/setting section 33.

The data transceiver 31 has a function to receive data from the datainput/output device 2 and a function to transmit data to the datainput/output device 2.

The data analysis section 32 has functions to analyze data and tospecify the buffer to be defined in relation to the service class. Inother words, it defines which of the buffers to be set (or related) tothe service class. In addition, the data analysis section 32 has afunction to specify the buffer whose definition data should be read.

The data reading/setting section 33 has a function to define a certainbuffer, within the buffer section 11 of the ATM buffer device 1, to beset (or related) to the service class. Or, it has a function to readdefinition data from the certain buffer.

Next, operations of the ATM switch will be described in detail withreference to the aforementioned block diagrams of FIGS. 1A, 1B and 1C aswell as a flowchar of FIG. 2.

In step S41, the data input section 21 of the data input/output device 2inputs data of a service class, which are forwarded to the datatransceiver section 22 in FIG. 1B.

In step S42, the data transceiver section 22 transmits the data to thedata processing device 3 in FIG. 1C.

In step S43, the data transceiver section 31 of the data processingdevice 3 receives the data from the data input/output device 2, so thatthe data are forwarded to the data analysis section 32.

In step S44, the data analysis section 32 analyzes the data so as tospecify items of the data such as request type, buffer number andservice class (i.e., service category and quality of service (QOS)class).

Suppose that the data analysis section 32 analyzes the data whether todesignate a setting request or a read request for a buffer number “1”with respect to a certain service class (e.g., service category: CBR,QOS class: 1), for example. In that case, the data analysis section 32forwards the data to the data reading/setting section 33 in response tothe request type, which is either the setting request or the readrequest. That is, the data processing device 3 transfers control fromstep S45 to step S46 or step S47.

At a setting request mode corresponding to the setting of the data, thedata processing section 3 proceeds to the step S46, wherein the datareading/setting section 33 sets the service class to the buffer whosebuffer number is specified within the buffer section 11 of the ATMbuffer device 1. Then, the content of such processing of the datareading/setting section 33 is supplied to the data transceiver section31.

At a read request mode corresponding to the reading of the data, thedata processing section 3 proceeds to the step S47, wherein the datareading/setting section 33 reads the service class of the buffer whosebuffer number is specified within the buffer section 11 of the ATMbuffer device 1. Then, the read service class is supplied to the datatransceiver section 31 together with the buffer number.

In step S48, the data transceiver section 31 receives the data from thedata reading/setting section 33, so that the data are transmitted to thedata input/output device 2.

In step S49, the data transceiver section 22 of the data input/outputdevice 2 receives the data from the data processing device 3, so thatthe data are forwarded to the data output section 23.

Thereafter, the data input/output device 2 transfers control to stepS50. That is, at the mode of the setting of the data, the data outputsection 23 displays processing results in the setting. At the mode ofthe reading of the data, the data output section 23 displays contents ofthe read data.

Next, the operations of the ATM switch will be described in furtherdetail with reference to a flowchart of FIG. 3, which shows a concreteexample in the setting of the data.

In step S61, the data input/output device 2 inputs data, which designatepieces of information as follows:

Request Type: Setting

Buffer Number: 1

Service Category: CBR

QOS Class: 1

In the above, the QOS class (i.e., quality-of-service class) is definedby cell delay, cell delay variation and cell discard ratio, for example.In addition, the QOS class “1” corresponds to the class that assures acertain level of service quality such as the quality of video ofconstant rate, for example.

Incidentally, it is possible to define only the service category withoutdesignating the QOS class.

The aforementioned data are transmitted from the data input/outputdevice 2 by means of the data transceiver section 22 in step S62. Instep S63, the data are received by the data processing device 3.

In the data processing device 3, the data are delivered to the dataanalysis section 32. In step S64, the data analysis section 32 analizesthe request type of the data. In step S65, a decision is made as towhether the data are related to a data read mode or not.

As described above, the present data designate the “setting of data” asthe request type. So, the data processing device 3 transfers control tostep S66. Thus, the data are set to the designated buffer whose buffernumber is “1”, wherein the ATM switch defines the service category ofCBR and the QOS class “1” with respect to the designated buffer.

In the data setting mode, it is possible to change and delete definitionof the service class other than addition of definition with respect tothe buffer.

Thereafter, processing results of the data are transmitted from the dataprocessing device 3 by means of the data transceiver 31 in step S67.Thus, the data input/output device 2 receives the processing results ofthe data in step S68.

In this case, the processing results of the data indicate that noservice class is defined with respect to the buffer of the buffer number“1”, for example. In other words, result of the setting is “OK” (orcompleted). So, the data output section 23 of the data input/outputdevice 2 displays contents of the data together with the buffer number“1” in step S69.

If some service class has been already defined with respect to thebuffer number “1”, result of the setting is “NG”. So, the service classwill be defined with respect to a buffer of a different buffer number.

FIG. 4 is a flowchart showing operations of the ATM switch with respectto the data read mode.

In step S71, the data input/output device 2 inputs data, which designatepieces of information as follows:

Request Type: Read

Buffer Number: 1

The aforementioned data are transmitted from the data input/outputdevice 2 by means of the data transceiver section 22 in step S72. Instep S73, the data processing device 3 receives the data.

In the data processing device 3, the data analysis section 32 analyzesthe data with respect to the request type in step S74. In step S75, adecision is made as to whether the data designate the data read mode ornot.

In this case, the data designate the data read mode. So, the datareading/setting section 33 reads data of the service class which isdefined with respect to the buffer of the buffer number “1” in step S76.

Suppose a concrete example shown in FIG. 5, in which the service classis concretely defined with respect to the buffer 1 within the buffersection 11 shown in FIG. 1. In this example, data of the service classrepresenting the service class of “CBR” and QOS class “1” (or “QOS1”)are defined with respect to the buffer 1 having the buffer number “1”.So, such data are transmitted from the data processing device 3 by meansof the data transceiver section 31 in step S77. In step S78, the datainput/output device 2 receives the data.

In step S79, the data output section 23 displays contents of the data ofthe service class, representing the service category of CBR and QOSclass “1”, which is defined with respect to the buffer number “1”.

If no service class is defined with respect to the buffer 1 of thebuffer number “1”, the data output section 23 displays a message that noservice class is defined with respect to the buffer number “1”.

With reference to FIG. 6, a description will be given with respect tothe ATM switch in accordance with another embodiment of the invention.

FIG. 6 is a block diagram showing a configuration of selected parts ofthe ATM switch of another embodiment of the invention. This ATM switchis basically configured similar to the aforementioned ATM switch shownin FIGS. 1A, 1B and 1C. As compared with the aforementionedconfigurations shown in FIGS. 1B and 1C, the ATM switch shown in FIG. 6is characterized by further providing data storage sections 24 and 34 inthe data input/output device 2 and the data processing device 3respectively.

The data storage section 24 has a function to store “new” data of a newservice category and a new QOS class, which are designated inside of thedata input/output device 2.

In addition, it has another function to delete “unnecessary” data of theservice category and QOS class, which are not required anymore.

Similarly, the data storage section 34 has a function to store “new”data of a new service category and a new QOS class, which are designatedinside of the data processing device 3.

In addition, it has another function to delete “unnecessary” data of theservice category and QOS class, which are not required anymore.

Next, operations of the ATM switch shown in FIG. 6 will be described indetail with reference to a flowchart of FIG. 7.

In step S81, the data input/output device 2 inputs data by means of thedata input section 21. In step S82, a decision is made as to whether theinput data are related to a data renewal mode or not. In the case of thedata renewal mode in which addition or deletion is performed withrespect to the service class, the data input/output device 2 transferscontrol to step S83, wherein the data are supplied to the data storagesection 24. The data are renewed with respect to the service category orQOS class and are stored in the data storage section 24. Then, the dataare supplied to the data transceiver section 22.

If the input data are not related to the data renewal mode, the datainput/output device 2 transfers control from step S82 to step S84.Herein, the data are supplied to the data transceiver section 22. Thus,the data transceiver section 22 transmits the data to the dataprocessing device 3.

In step S85, the data processing device 3 receives the data by means ofthe data transceiver 31. Then, the data are forwarded to the dataanalysis section 32.

In step S86, the data analysis section 32 analyzes the data. In stepS87, a decision is made as to whether the data are related to a datarenewal mode or not. In the case of the data renewal mode in whichaddition or deletion is performed with respect to the service class, thedata processing device 3 transfers control to step S88, wherein the dataare supplied to the data storage section 34.

The data are renewed with respect to the service category or QOS classand are stored in the data storage section 34. Then, the data aresupplied to the data transceiver section 31.

If the data are not related to the data renewal mode, the dataprocessing device 3 transfers control from step S87 to step S89. Herein,the data processing device 3 specifies the request type, buffer numberand service class (i.e., service category and QOS class) with respect tothe data. For example, the data processing device 3 analyzes the data todesignate a setting request or a read request for buffer number “2” withrespect to a certain service class (e.g., service category: rtVBR, QOSclass: 2). So, the data are supplied to the data reading/setting section33 in response to the setting request or read request.

In the case of the setting request corresponding to the setting of data,the data processing device 3 transfers control from step S89 to stepS90. Herein, the data reading/setting section 33 sets the service classto the buffer whose buffer number is specified within the buffer section11 of the ATM buffer device 1. Then, processing result is supplied tothe data transceiver section 31.

In the case of the read request corresponding to the reading of data,the data processing device 3 transfers control from step S89 to stepS91. Herein, the data reading/setting section 33 reads the service classof the buffer whose buffer number is specified within the buffer section11 of the ATM buffer device 1. Then, the service class is supplied tothe data transceiver section 31 together with the buffer number.

Thus, the data transceiver section 31 receives the data from the datareading/setting section 33 and the data storage section 34. In step S92,the data transceiver section 31 transmits the data to the datainput/output device 2.

In step S93, the data input/output device 2 receives the data by meansof the data transceiver section 22. Then, the data are supplied to thedata output section 23.

In step S94, the data output section 23 performs a display process. Thatis, the data output section 23 displays the processing result in settingof the data in response to the setting request, while it displays theread data in response to the read request. At the data renewal mode, thedata output section 23 displays the processing result in renewal of thedata.

Next, FIG. 8 is a flowchart showing another example of operations of theATM switch of FIG. 6 at the data renewal mode.

In step S101, the data input/output device 2 inputs data. In step S102,a decision is made as to whether a request type of the data correspondsto data renewal or not. Now, suppose that a new service categorycorresponds to “UBR2” which is provided by adding a minimum (bit) rateassurance to “UBR”, for example.

In the above case, the data input/output device 2 transfers control tostep S103. Herein, the data are renewed (or added) and are stored in thedata storage section 24. Then, the data are supplied to the datatransceiver section 22. In this case, the data input section 21 sensesstored content of the data. Thereafter, it becomes possible to designatea new service category. In step S104, the data input/output device 2transmits the data by means of the data transceiver section 22. In stepS105, the data processing device 3 receives the data.

In step S106, the data analysis section 32 analyzes the request type ofthe data. In step S107, a decision is made as to whether the requesttype of the data corresponds to data renewal or not.

In this case, the request type of the data corresponds to the datarenewal, so the data processing device 3 transfers control to step S108.That is, the data are renewed (or added) and stored in the data storagesection 34. Then, the data are forwarded to the data transceiver section31.

Incidentally, the data reading/setting section of the data processingdevice 3 and the aforementioned ATM buffer device 1 sense stored contentof the data. Thereafter, it becomes possible to define a new servicecategory.

Then, the data processing device 3 transmits processing result of thedata in step S109. In step S110, the data input/output device 2 receivesthe data.

The aforementioned processing result indicates renewal of the servicecategory, wherein the new service category is added and stored. So, instep S111, the data output section 23 displays renewed content of thedata because the data renewal is certainly completed so that theprocessing result in data renewal is “OK”.

By the way, if the same of the new service category has been alreadyadded to the data storage sections 24 and 34, the data renewal isincomplete so that the processing result in data renewal is “NG”. Thus,the data output section 23 displays a message indicating “NG” in thedata renewal.

As described heretofore, this invention has a variety of technicalfeatures and effects, which can be summarized as follows:

-   -   (1) This invention is capable of defining the service class,        input by the data input section, for the corresponding buffer        within the ATM switch by means of the data setting section. So,        the user is capable of freely defining the service classes for        the buffers within the ATM switch. As a result, it is possible        to improve usability of the ATM switch.    -   (2) The user is capable of adding, changing or deleting the        service class for the buffer within the ATM switch. This further        improves the usability of the ATM switch. In addition, it is        possible to delete “unnecessary” service classes. So, it is        possible to efficiently use the resources (e.g., buffers) of the        ATM switch.    -   (3) This invention is designed such that the user is capable of        requesting the data reading section of the ATM switch to read        data from the buffer whose buffer number is displayed by the        data output section. So, it is possible for the user to execute        reading of the service class with respect to the buffer within        the ATM switch. As a result, it is possible to improve        maintenance of the ATM switch.    -   (4) This invention is designed such that the data input/output        device and data processing device are equipped with the data        transceiver sections respectively. So, it is possible to perform        defining and reading on the service classes of the buffers of        the ATM switches respectively by means of the ATM network. As a        result, it is possible to improve maintenance of the ATM        switches as well as usability of the ATM network.    -   (5) This invention is designed such that data regarding the new        service class and new QOS class are renewed and are stored in        the data storage section(s). So, the ATM switch is capable of        coping with the new service category and new QOS class smoothly.        As a result, it is possible to improve extendibility of the ATM        switch and ATM network.

As this invention may be embodied in several forms without departingfrom the spirit of essential characteristics thereof, the presentembodiment is therefore illustrative and not restrictive, since thescope of the invention is defined by the appended claims rather than bythe description preceding them, and all changes that fall within metesand bounds of the claims, or equivalence of such metes and bounds aretherefore intended to be embraced by the claims.

1. A multi-service-class definition type switch comprising: a bufferdevice which comprises a buffer section having a plurality of buffersand a cell reading section for reading data from the buffer section; adata input/output device which comprises a data input section forinputting data from an external source, a data output section foroutputting the data, and a first data transceiver section for performingreception and transmission with respect to the data; a data processingdevice which comprises a second data transceiver for performingreception and transmission of data in connection with the first datatransceiver section, a data analysis section for analyzing the datareceived from the second data transceiver section, and a datareading/setting section; wherein the data input/output device is capableof inputting and outputting, data regarding a service class of a buffer,comprising at least one of a service category and a QOS class; andwherein the data processing device is capable of adding and storing newdata regarding at least one of a new service category and a new QOSclass.
 2. A multi-service-class definition type switch according toclaim 1 wherein the data processing device performs processing regardingreception, transmission and analysis on data regarding a service class,a buffer number and a request type, so that reading and setting of thedata can be made with respect to a prescribed buffer selected from thebuffer section in response to a result of the processing.
 3. Amulti-service-class definition switch according to claim 1, wherein theswitch is an ATM switch.
 4. A multi-service-class definition type switchcomprising: a buffer device which comprises a buffer section having aplurality of buffers and a cell reading section for reading data fromthe buffer section; a data input/output device which comprises a datainput section for inputting data from an external source, a data outputsection for outputting the data, and a first data transceiver sectionfor performing reception and transmission with respect to the data; anda data processing device which comprises a second data transceiver forperforming reception and transmission of data in connection with thefirst data transceiver section, a data analysis section for analyzingthe data received from the second data transceiver section, and a datareading/setting section; wherein the data input/output device is capableof inputting and outputting data regarding a service class of a buffer,comprising at least one of a service category and a QOS class; whereinthe data processing device is capable of adding and storing new dataregarding at least one of a new service category and a new QOS class;and wherein the data input/output device comprises a graphical userinterface that displays at least one of the new service category and newQOS class.
 5. A multi-service-class definition type switch comprising: adata input/output device, comprising a data input section and a dataoutput section; a data processing device, comprising: a transceiversection for receiving and transmitting data to and from said datainput/output device, a data analysis section for analyzing the datareceived from said data transceiver section, and a data reading/settingsection; and a buffer device comprising: a plurality of buffers, atleast one of which has not previously been assigned a service class anda cell reading section; wherein said input/output device is capable ofreceiving data comprising a new service class and transmitting said datato said data processing device, and wherein said data reading/settingsection is capable of assigning the new service class to one of said atleast one buffer which has not previously been assigned a service class.